Renewable tip hammer assembly



Feb. 20, 1962 l.. K. KNIGHT 3,022,018

RENEWABLE TIP HAMMER ASSEMBLY Filed July 19, 1960 LLOYD K'. KNIGHT, BY

W ww l2 HTTY United The instant invention relates to a renewable tiphammer for use in a pulverizer, in which the hammer may be removed fromthe shank by which the hammer is mounted in the pulverizer to permitreversal of the hammer or replacement thereof.

lt is an object of the instant invention to provide an improvedrenewable tip hammer assembly in which the hammer may readily be removedfrom the hammer assembly.

It is another object of the instant invention to provide an improvedrenewable tip hammer assembly in which the hammer may be readilyreplaced after it has been worn down, or may be reversed after onehammer face has been worn down.

It is a further object of the instant invention to provide an improvedrenewable tip hammer assembly in which the elements thereof aremaintained in assembly by a locking pin that may be readily removed fordisassembly of the elements.

It is still another object of the instant invention to provide animproved renewable tip hammer assembly in which the several elementsthereof are maintained in assembly by a spring locking pin that may bereadily removed for disassembly of the elements.

A still further object of the instant invention is to provide animproved renewable tip hammer assembly in which the elements thereof aresecured in assembly by a locking pin, which is enclosed within thehammer to protect the locking pin from damage during the operation ofthe hammer assembly.

It is also an object of the instant invention to provide an improvedhammer assembly in which the several elements thereof are looselyassembled and are secured in assembly by a locking pin rmly secured toone of the elements of the hammer assembly.

Other objects of the invention will appear hereinafter, the novelfeatures and combinations being set forth in the appended claims.

In the accompanying drawings:

FIG. 1 is a side elevational view of a hammer assembly constructed inaccordance with the instant invention;

FIG. 2 is a rear elevational view, partially in section, of the hammerassembly;

FIG. 3 is a sectional view of the hammer assembly taken on the line 3 3in FIG. 2;

FIG. 4 is a sectional view of the hammer assembly taken on the line 4--4in FIG. 2;

FlG. 5 is a side elevational View, partially in section, of a modifiedform of the hammer assembly constructed in accordance with the instantinvention; and

FIG. 6 is a front elevational view, partially in section, 0f the hammerassembly illustrated in FIG. 5.

Referring to FIGS. l to 4 of the drawings, there is illustrated oneembodiment of a hammer assembly 10, constructed in accordance with theinstant invention. The hammer assembly is adapted to be utilized in apulverizer having a rotor of a known form comprising several axiallyspaced rotor discs mounted on a shaft by which the rotor is rotated. Aplurality of circumferentially spaced hammer rods extend in an axialdirection through the rotor discs at positions adjacent the periphery ofthe rotor discs, and the hammer assembly 10 is mounted on a hammerassembly mounting rod 11, as illustrated in the drawings herein.

arent 3,022,9l8 Patented Feb. 20, 1962 The hammer assembly 10 has a pairof similar shanks 12, which are spaced from each other in an axialdirection. Each shank 12 is formed with a bore 13 at one end thereof,which is of somewhat larger diameter than the hammer assembly mountingrod 11, so that the Shanks 12 lit loosely on the rod 11. Upon rotationof the rotor including the hammer assembly mounting rod 11, the hammerassembly 10 will take a radial position with respect to the rotor byoperation of centrifugal force. When the rotor is stationary the hammerassembly 10 will be suspended loosely on the hammer assembly mountingrod 11.

A hammer 15 is adapted to be mounted on the lower ends of the shanks 12.Each shank 12 is formed with a tongue 16 which is inset from theopposite faces 17, 18 of the shank 12. The hammer 15 includes a pair ofrecesses 19, which are spaced from each other, and are complementallyformed with respect to the tongues 16 of the Shanks 12. The recesses 19are somewhat larger than the tongues 16 for a loose tit of the hammer 15on the Shanks 12. The recesses 19 are spaced from each other, as seen inFIG. 2, and the walls 20, 21 are provided at the opposite sides of eachrecess 19.

The tongue 16 of each shank 12 is provided with a bore 22, and each wall20, 21, at the opposite sides of the recesses 19, is similarly formedwith a bore 23. The several bores 22, 23 in the shanks 12 and in thehammer 15, respectively, are of the same diameter and are adapted to bealigned with each other when the tongues 16 are received within therecesses 19. A hammer supporting pin 24 extends through the bores 22, 23and serves to connect the hammer 15 to the shanks 12, and therebysupports the hammer 15 on the Shanks 12. Each of the bores 22, 23 has asomewhat larger diameter than the hammer supporting pin 24 for a loosefit of the hammer supporting pin 24 in the several bores 22, 23.

The hammer 15 is formed with a cavity 25 disposed between the innerwalls 26, as best seen in FIGS. 2 and 4. The hammer supporting pin 24extends through the cavity 25, and is formed with a transverselyextending Ibore 26, which intersects the axis of the hammer supportingpin 24. The hammer 15 includes bores 27, 28, which are aligned with eachother and with the bore 26 in the hammer supporting pin 24. The bores27, 23 are of somewhat larger diameter than the bore 26. A cylindricalspring locking pin 29 is inserted into the bore 26 of the hammersupporting pin 24. The bore 26 is of such diameter that the locking pin24 must be press fitted into the bore 26 for securelyl holding thelocking pin 29 in the bore 26. The bores 27, 2% in the hammer 15 provideaccess to the bore 26 for insertion of the locking pin 29 therein, andalso permit removal of the locking pin 29. The spring locking pin 29 isof such length that it extends into the bores 27, 28 of the hammer 15,and thereby prevents the hammer supporting pin 24 from working out ofthe ha-mmer assembly 1l) in an axial direction. It will be understoodthat since the bores 27, 2S are of somewhat larger diameter than thelocking pin 26 there may be some axial movement of the hammer supportingpin 24, the maximum amount of such movement being equal to the dierencein diameter of the locking pin 29 and the bores 27, 2S. However, suchaxial movement o-f the hammer supporting pin 24 is so Small that thereis no possibility of aecting the assembly of the hammer 15 on the Shanks12 as described herein.

The cylindrical spring locking pin 29, which is illustrated in thedrawings, is of a type that is formed as a tube which is split along oneside thereof. In applying the locking pin to a bore, such as the bore26, the locking pin 29 is compressed and is thereby secured in the boreto which it is applied. It will be understood that the cyiindricalspring locking pin 29, which is illustrated in the drawings, is only oneexemplary form of this device, and other locking pins may be utilized in30, 31 of the hammer 15 extend upwardly around the tongues 16 of theVShanks 12, and there is provided a substantial thickness of hammermaterial around the tongues 16 to protect the latter during operation ofthe i hammer assembly 1Q. As seen in FIG. 4, the opposite ends of thelocking pin 29 are disposed a substantial distance inwardly from thefront and rear faces 30, 31 of the hammer 15 to protect the locking pin29 and to preventk damage thereto during operation of the hammerassembly 10. Thus, it isV always possible to readily remove the lockingpin 29. The several elements of the hammer assembly are looselyassembled with respect to each other to prevent the elements fromfreezing together as a result of the impact forces brought to bear onthe hammer assembly 10 during operation of the latter. lThis facilitatesdisassembly of the elements of the -hammer assembly 10. The Shanks 12and the hammer15 are symmetrically formed so thatrwhen the front lface3G of the hammer 15 is worn, the hammer 15 may be removed from theShanks 12 and replaced on the Shanks 12 in reverse position, whereby therear face 31 will then be the operating face of the hammer 15.

In` FIGS. 5 and 6 there is illustrated a hammer assem- Y bly 35 which isanotherembodiment of the instant invention, and is a modified form ofthe structure illus- Vtrated in FIGS. 1 to 4. The hammer assembly 35 isadapted toV be mounted on a hammer assembly mounting rod 36 which isincluded in a'pulverizer rotor `by which the hammer assembly 35 isrevolved.

The hammer assembly 35 includes a single shank 37 formed with a bore 38at one end thereof by which the hammer assembly 35 is mounted on the rod36. The bore 38 is of somewhat larger diameterA than the rod 36forrloosely mounting the hammer assembly 35 on the rod 36. In operationof the hammer assembly 35 it will take a radial position with respect tothe pulverizer rotor by the action of centrifugal force. Y

The shank 37 includes a tongue 39 which is insetfrom the opposite faces40, 41 of the shank 37. The hammer 42 is for-med with a centrallydisposed recess 43, which is adapted to receive the tongue 39.V Therecess 43 is complementally formed with respect to the tongue 39, and issomewhat larger than the `tongue 39 for a loose it of the tongue 39 inthe recess 43. The hammer 42 includes walls 44, 45 disposed at oppositesides of the recess 43, and serving to protect the tongue 39 duringoperation of the hammer assembly 35. Y

A -bore 46 is formed in the tongue 39, and bores 47 are formed in thewalls 44, 45. The several bores 46, 47 are axially aligned with eachother and are of the same diameter. A hammer supporting pin 4S extendsthrough the bores 46, -47 for joining the hammer 42'to the shank 37 andsupporting the hammer 42 on the shank 37. The bores 46, `47 are ofsomewhat larger diameter than the pin 48 for a loose t of the latter inthe bores 46, 47.

The hammer supporting pin 48 has a transversely ex-Y tending bore 49which intersects the axis of the pin 48. The tongue 39 of the shank 37is formed with bores 50,51 at the opposite sides of the hammersupporting pin 48 and disposed in alignment with the bore 49. The 7hammer 42 is formed with bores 52, 53 which are alsothe bore 49 of thehammer supporting pin 48, and is of such size that it is press iittedinto the bore 49 to Vbe securely held therein. j

The cylindrical spring locking pin 54 holds the several elements of thehammer assembly 35 together by preventing axial movement of the hammersupporting pin 48. As seen in FIG. 5, thelocking pin 54 is of suchlength, that at the opposite sides of the hammer supporting pin 4S, thelo-cking pin 54 extends into the bores 5G, 51, 52, 53. Since the boresSil, 51,52, 53 are of somewhat larger dia-meterethan the locking pin 54,there may be a limited amount of axial movement of the hammer supportingpin 48, but this will be sosmall as to prevent the elements ofthe-hammer assemblyr35 from separating.

The several elements of the hammer assembly 35 are loosely assembledwith Aeach other to facilitate disassembly thereof for removal of thehammer 42. The locking pin 54 is compressed when it is secured in thebore 49 of the hammer supporting pin 48, and is securely Vheld in thehammer supporting pin 48. However, the locking pin 54 is loose withrespect to the shank 37 and the hammer 42, and may be readily removedfrom the hammer supporting pin 48 throughrthe bores 50, 51, 52, 53 whichprovide access to the'locking pin 54.

As viewed in FIG. 5, the hammer assembly 35 is ref volved in a clockwisedirection, asY indicated by the arrow.

The hammer 42 has a front face 55 and a rear face 56. Y

VIn the operation of the hammer assembly 35, as described, the frontface 55 Vof the hammer 42' will be the operating ,face of the latter,and the rear face 56 will be the inactive face thereof. The hammer 42andthe shank 37 are each symmetrical, so that when the front face 55 hasbecome Worn the hammer 42 may be readily removed from the shank 37 andre-assembled in reverse position Vto make the rear face 56'the operatingface of the hammer42. When both faces 55, 56 of the hammer 42 havebecome worn, the hammer 42 may be replaced by another hammer. The hammerfaces 55, 56 extend upwardly around the tongue 39 of the shank 37 andprovide a substantial thickness of hammer material around the tongue39xfor protection of the latter during operation of the hammer assembly35. Since the locking pin 54 is inset from the hammer faces 55, 56, italso is protected during operation of the hammer.V

By the instant invention there is provided an improved renewable tiphammer assembly in which the hammer may be readily removed from theshank on which therhammer is mounted. The several elements of the hammerassembly are held together by a locking pin that may be readily removedfrom the assembly, when Vthe hammer hassbecome worn and it is. desiredto remove the latter from the hammer assembly. The locking pin isprotected by the hammer during the operation of the hammer assembly sothat it cannot be damaged, thereby facilitating the removal of thelocking pin when it is desired Yto disassemble the hammer assembly. Y Yf ObviouslyV those skilled in the art may'make various vchanges in thedetails and arrangement of parts without departing from the spirit andscope of the invention as defined by the claims hereto appended, andapplicant thereforewishes not to Ybe restricted to the preciseconstruction herein disclosed.

' Vthe pulverizer, a hammer adapted to be secured to the Shanks, each ofsaid Shanks including a hammer mounting tongue, said hammer including apair of lspaced recesses each adapted to receive one of said tongues, ahammer supporting pin extending through'the hammer and said tongues andloosely received in the hammer and tongues for holding Vthe hammer onthe Shanks, a transverse bore in said hammer supporting pin, a lockingpin secured in said transverse bore to maintain the hammer supportingpin in assembly with the shanks and hammer, said transverse bore andlocking pin being disposed intermediate the hammer recesses, and a borein the hammer aligned with said transverse bore to provide access tosaid transverse bore for insertion of the locking pin into saidtransverse bore, said hammer bore being substantially larger than thelocking pin.

2. A renewable tip hammer assembly for a pulverizer comprising a shankfor mounting a hammer in the pulverizer, a hammer adapted to be securedto the shank, said shank including a hammer mounting tongue, said hammerincluding a recess to receive said tongue, a hammer supporting pinextending through the hammer and tongue and loosely received in thehammer and tongue for holding the hammer on the shank, a transverse borein said hammer supporting pin formed on an axis intersecting the tongue,a locking pin secured in said transverse bore to maintain the hammersupporting pin in assembly with the shank and hammer, and aligned boresin the hammer and tongue formed on the axis of said transverse bore andaligned therewith to provide access to said transverse bore forinsertion of the locking pin into said transverse bore, said alignedbores in the hammer and tongue being substantially larger than thelocking pin.

3. A renewable tip hammer assembly for a pulverizer comprising a shankfor mounting a hammer in the pulverizer, a hammer adapted to be securedto the shank, said shank including a hammer mounting tongue, said hammerincluding a recess to receive said tongue, said hammer recess and saidtongue being of such relative size that the tongue ts loosely within thehammer recess, a hammer supporting pin extending through the hammer andtongue and loosely received in the hammer and tongue for holding thehammer on the shank, a transverse bore in said hammer supporting pin, alocking pin secured in said transverse bore to maintain the hammersupporting pin in assembly with the shank and hammer, a bore in thehammer aligned with said transverse bore to provide access to saidtransverse bore for insertion of the locking pin into said transversebore, and said hammer bore being substantially larger in diameter thanthe locking pin.

4. A renewable tip hammer assembly for a pulverizer comprising a shankfor mounting a hammer in the pulverizer, a hammer adapted to be securedto the shank, said hammer including a recess to receive said shank, ahammer supporting pin extending through the hammer and shank for holdingthe hammer on the shank, a transverse bore in said hammer supportingpin, a spring locking pin press fitted in said transverse bore andsecured therein to maintain the hammer supporting pin in assembly withthe shank and hammer, and a bore in the hammer aligned with saidtransverse bore to provide access to said transverse bore for presslittng the locking pin, said hammer bore being substantially larger thanvthe locking pin into said transverse bore.

References Cited in the tile of this patent UNITED STATES PATENTS1,166,698 Lincoln Jan. 4, 1916 1,693,058 Shelton Nov. 27, 1928 Y1,940,116 Brooks Dec. 19, 1933 FOREGN PATENTS 683,171 Germany Oct. 31,1939 891,047 Germany Sept. 24, 1953

